Multidrug-resistant Vibrio species isolated from abattoir effluents in Nigeria

Abstract

Introduction: The antibiograms of Vibrio species isolated from abattoir effluents in the Niger Delta region of Nigeria were investigated with respect to their public health significance. Methodology: Vibrio species were isolated and identified using standard microbiological and molecular techniques, while antibiogram of isolates was tested and interpreted using the disk diffusion method described by the Clinical and Laboratory Standards Institute. Results: Of 150 presumptive isolates, 48 (32%) were confirmed to be Vibrio spp. by PCR; of these, 23 (47.9%) were V. cholerae, 11 (22.9%) were V. fluvialis, 8 (16.7%) were V. vulnificus, and 6 (12.5%) were V. parahaemolyticus. The antibiogram revealed that Vibrio species were generally resistant to ampicillin (60%–67%), trimethoprim (80%–100%), and tetracycline (60%–83%), whereas they were sensitive to ceftriaxone (86%–100%), the aminoglycosides (67%–100%), imipenem (86%–100%), ofloxacin (83%–100%), and chloramphenicol (67%– 100%). The isolates exhibited multiple antibiotic resistance (MAR) with an average MAR index of 0.23. Conclusions: This study demonstrated that abattoir effluents are important reservoirs for multidrug-resistant Vibrio species that might be considerable contributors to the recurrent episodes of epidemic cholera and non-Vibrio cholera infections in Nigeria.